In the cleaning industry, cleaning or foaming compounds in the form of an aqueous solution are often applied to dirty surfaces to extract dirt, oil, stains, bacteria, and other contaminants from the surfaces. For example, cleaning compounds, such as soaps, detergents, and surfactants, are used for extracting contaminants from the surface of a textile. Generally, such cleaning compounds are effective because their chemical structures include both polar (hydrophilic) and non-polar (hydrophobic) components. Therefore, cleaning compounds can be combined with a polar solvent, such as water, and are capable of dissolving and extracting non-polar solutes, such as oil, grease, dirt, and other contaminants. Once the contaminants have been extracted from the textile, the solution, now holding the suspended contaminants, can then be lifted from the textile and expelled, thus leaving behind a clean surface.
In conventional cleaning systems, the expelled cleaning solution with the suspended contaminants is often pumped or suctioned into a waste tank for temporary storage until the tank is emptied and the used cleaning solution disposed of. In such conventional systems, the solution often causes foam to build up in the waste tank. As the foam volume within the tank increases, the foam becomes susceptible to being suctioned out of the waste tank and into the vacuum blower, which can damage the blower. Additionally, any foam entering the blower can be blown or discharged out of the blower and into surrounding areas, which can soil and damage to those areas. In order to avoid the complications of foam build-up in conventional cleaning systems, users may have frequently empty the waste tank, thus resulting in bothersome and inefficient delays in the cleaning process.
Conventionally, compounds known as defoamers or defoaming agents have been employed in certain applications to reduce the build-up and formation of foam. Defoaming agents are generally liquids or powders that disperse quickly throughout aqueous solutions. Although effective at knocking-down foam, conventional defoaming agents are not well suited for certain cleaning systems. For example, if a defoaming agent is added to the waste tank of a batch cleaning system, each time the contents of the waste tank are expelled, the dissolved defoaming agent is expelled as well. Accordingly, for some systems, each time the contents of the tank are expelled, more defoaming agent must be added to the waste tank for any subsequent batch. Also, in some continuous cleaning systems, where the waste tank is continuously emptied during the cleaning process, the user must repeatedly add more defoaming agent during a single cleaning operation. Therefore, while the use of defoaming agents in some cleaning systems may be useful for reducing foam build-up, because conventional defoaming agents and systems require users to repeatedly add more defoaming agent, the increased cost, inefficiency, and difficulty of utilizing such conventional defoaming agents in known cleaning systems results in a bothersome, wasteful, and generally ineffective cleaning process.
In response to the drawbacks of conventional defoaming agents, some solid defoaming agents have been engineered to melt at low temperatures. Once the solid defoaming agent with a low melting point is added to the waste tank, the user can controllably heat the waste tank solution to the melting point of the solid defoaming agent and allow the solid defoaming agent to melt into the aqueous solution. Even though such solid defoaming agents have shown to be more effective than conventional defoaming agents because the user has more control over the dispersion rate of the defoaming agent, the additional equipment, expense, and excess energy required to heat the waste tank solution makes the implementation of such solid defoaming agents impractical and inefficient.